基于IIC和云服务器的智能家居控制系统设计

智能家居普遍采用无线通信技术对家居进行互联,不同的通信方法对智能家居系统的稳定性、便捷性、可靠性有很大的影响;针对智能家居的访问方式,通过对比不同的无线通信技术,选择合适的技术运用在智能家居系统的设计中,实现局域网和广域网两种访问方式;在无线传输的智能家居基础上,使用IIC总线进行功能扩展,使用云服务器来替代传统计算机服务器,增加了系统的灵活性和手机访问的快捷性,更好地实现家庭住宅管理与监测,为我们平时的生活提供便利和保护。     

基于TD-LTE和Android技术的智能家居系统设计

随着科技水平和生活水平的提高,人们对居住环境提出了更高的要求,智能家居系统应运而生。本文设计了一种基于TD-LTE和Android系统的智能家居系统,该系统采用各种传感器监测家庭环境,并通过TD-LTE网络将信息传送至用户手机,用户通过Android客户端可以随时随地的掌握家居环境的情况。该系统利用了第四代移动通信技术和移动互联网技术,使得其数据通信速率大大提高,适用群体范围增大,可以远程监控家居设备,提供了安全、舒适和便捷的生活环境,极大的提升了家居生活品质。该系统硬件设备简单可靠,成本较低,易于扩展。     

基于ARM和nRF905组网的智能家居系统设计

针对家居中电器种类和数目繁多且分散于各室造成控制不便,提出了一种利用nRF905射频模块实现无线通信的智能家居控制系统。系统对射频数据传输协议进行了设计,给出了室内多个微控制器的组网方案。用户通过手机短信或万能遥控器把对家电的控制信号发送至基于ARM平台搭建的主控中心,再由主控中心发送至若干个通信节点或智能插座,万能遥控器通过射频信号实现对家电的近距离遥控,手机通过GSM通信实现对家电的远程遥控。通信节点基于STC89C52RC单片机设计,能够实现对多种红外家电的控制并具备安防报警功能,智能插座则用于控制非遥控家电。实验表明,该系统可使网络中各节点、插座得到有效的控制,数据传输稳定、功能丰富、可扩展性强,具备较高的应用价值。     

基于发布订阅的分布式监控主动消息交互研究

针对分布式调度监控系统的客户服务器处理效率不高的问题,利用发布订阅消息通信技术,结合公共信息模型,提出了一种分布式监控主动消息交互的新方法。对量测类信息流和控制类信息流进行了实时交互接口设计,融入JMS消息服务器消息主题和发布订阅传输交互模式。该方法在工程中进行了应用,以石德线为算例,进行模拟量和状态量信息的交互实验,完成了单点和多点信息的交互传输,实现了实时变位信息向监控画面的主动即时传输,为分布式调度监控处理提供了一种新的高效实现方法。     

基于光生编码超宽带信号的多用户通信系统

提出并验证了一种基于光学方法产生编码超宽带(UWB)信号的多用户通信系统,在发射端通过光纤直接传输用光学方法生成的UWB信号,在接收端对编码UWB信号进行相关运算,同时完成用户信息和数据信息的判决。系统具有简单扩容、易于接收、远距传输、可调谐性等优点。设计制作的多信道光纤光栅滤波器和色散光纤组合成的鉴频器是系统的核心器件。传输的信号用不同的码片组合来区分各个用户,系统只需调节激光波长来实现用户切换,产生了不同用户的光生编码UWB信号,并恢复出不同用户的信息,实现了多用户通信全过程。     

基于GHZ态的量子网络身份认证方案

利用量子力学中纠缠态的非定域关联性,提出了一种基于GHZ态的星型量子通信网络方案,该方案能有效地对用户身份进行认证,提高信息传输的安全性,实现任意站点间的量子通信.     

基于RFID的仪器通信和数据采集控制技术

目前舰船电子装备故障检测原始技术数据采集与传输控制是测试技术专家与现场技术人员之间信息交互的难题,本文提出了一种基于RFID的仪器通信和数据采集控制技术。依托RFID的无线组网技术,介绍了该仪器通信和数据传输控制系统的总体设计、软硬件组成与功能,引出仪器通信与数据传输过程中主控机的监听服务和并发设计等控制机制,从而论述了主控机与仪器的数据采集和传输情况。最后分析了整个系统应用时的上传、接收、存储、解析浏览和反馈的功能和效果。实验结果表明该该系统满足了组网维修系统信息传递、共享与复用的需求。     

基于嵌入式的智能家居之视频监控系统设计

针对视频监控系统在智能家居中对异常情况处理不够智能、响应速度较慢的问题,提出嵌入式视频监控端的方案;首先搭建嵌入式开发板的组成模块,选择摄像头并配置红外线反射模块;其次考虑到智能家居视频监控的特点,提出适合嵌入式环境的改进三帧差分算法,对出现的目标物体进行轮廓提取和阴影消除;最后根据性能指标对改进算法验证,同时通过GPRS技术把处理好的图像发送给家居主人;实验表明该系统能实时对不明物体做出智能判断,运行稳定,实现了智能家居安全防范目的。     

基于音频监控的婴儿智能监护系统设计

为解决目前婴儿智能监护产品对婴儿哭声识别不准确的问题,设计了能准确识别婴儿哭声的婴儿智能监护系统。使用RT5350芯片作为处理器,使用PAP7501芯片实现对视频信号和音频信号的采集。对系统移植了Linux内核,使用多线程编程技术编写了应用程序。通过提取梅尔频率倒谱系数作为特征参数,使用动态时间规整算法作为识别算法,实现了对婴儿哭声的准确识别。该系统可以与云服务器通信,实现婴儿哭声报警功能;该系统可以与用户的终端设备通信,实现视频数据和音频数据的传输。该智能监护系统极大地方便了用户对婴儿的监护。     

家居智能控制设计与研究

智能化住宅的核心就是智能家居系统,设计介绍了智能家居系统的基础--家庭总线系统(HBS)的协议及基本构造,以及基于家庭总线系统的家庭智能控制系统的工作原理和总体结构。该系统作为一个智能化系统,能进行集中或分布、本地或异地的监视、控制和事务管理,可以通过远程遥控来对家庭的家用电器组进行具体设置和智能控制。     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.